Tailored fiber placement utilizing functional thread

Abstract

The present invention provides a system and method for the application of a functional thread to secure roving or other fibers to a substrate, thereby forming a precursor to a resultant composite component structure having targeted, enhanced structural reinforcement. The functional thread may be comprised of one or more fibrous filaments or have a monofilament structure. The invention encompasses the sewing of this functional thread at varying stitch densities as function of component stress analysis, the mechanical stresses that the component will be subject to when exposed to the forces and loads associated with its intended use, and at least one physical or mechanical property of a functional thread. This variable stitch density serves to provide targeted, localized mechanical enhancement and reinforcement to the resultant composite structure.

What is claimed is: 
     
       1. A system for applying a functional thread to a tailored fiber placement component precursor comprising:
 a component stress analysis memory storing data indicative of a strength of at least one subsection of the tailored fiber placement component being fabricated and a mechanical stress that the at least one subsection of the tailored fiber placement component will be subject to when the tailored fiber placement component is exposed to one or more forces and one or more loads associated with an intended use of the tailored fiber placement component; 
 a functional thread characteristic memory storing data indicative of at least one physical or mechanical property of a functional thread; 
 an augmentation processor adapted to perform a comparative analysis utilizing the data stored in the component stress analysis memory; and 
 a microprocessor-controlled embroidery system adapted to position at least one layer of roving upon a substrate in accordance with a predefined pattern, and to secure to the substrate a portion of the roving corresponding to the at least one subsection of the tailored fiber placement component with a stitching of the functional thread, wherein the functional thread has a stitch density which is determined as a function of the comparative analysis and the data stored in the functional thread characteristic memory. 
 
     
     
       2. The system of  claim 1 , wherein finite element analysis is utilized to compute the data indicative of the strength of the at least one subsection of the tailored fiber placement component being fabricated and the mechanical stress that the at least one subsection of the tailored fiber placement component will be subject to when the tailored fiber placement component is exposed to the one or more forces and the one or more loads associated with the intended use of the tailored fiber placement component. 
     
     
       3. The system of  claim 1 , wherein the microprocessor-controlled embroidery system is adapted to independently position a roving pipe and a sewing head in three-dimensions as a function of the predefined pattern and the determined stitch density. 
     
     
       4. The system of  claim 3 , wherein the embroidery system further controls a speed at which a needle stitches the functional thread to secure to the substrate the portion of the roving corresponding to the at least one subsection of the tailored fiber placement component, wherein a rate at which one or more individual stitches are executed is controlled as a function of the comparative analysis and the data stored in the functional thread characteristic memory. 
     
     
       5. A method for applying a functional thread to a tailored fiber placement component precursor comprising:
 computing a strength of at least one subsection of the tailored fiber placement component being fabricated; 
 computing a mechanical stress that the at least one subsection of the tailored fiber placement component will be subject to when the tailored fiber placement component is exposed to one or more forces and one or more loads associated with an intended use of the tailored fiber placement component; 
 determining at least one physical or mechanical property of a functional thread; 
 performing a comparative analysis between the computed strength of the at least one subsection of the tailored fiber placement component and the mechanical stress that the at least one subsection of the tailored fiber placement component will be exposed to; 
 computing a stitch density of the functional thread, based upon the at least one physical or mechanical property and the comparative analysis, to augment the strength of the at least one subsection of the tailored fiber placement component; and 
 controlling an embroidery system to position at least one layer of roving upon a substrate in accordance with a predefined pattern, and to secure to the substrate a portion of the roving corresponding to the at least one subsection of the tailored fiber placement component with a stitching of the functional thread, wherein the stitch density of the functional thread is equal to the computed stitch density. 
 
     
     
       6. The method of  claim 5 , wherein finite element analysis is utilized to compute the strength of at least one subsection of the tailored fiber placement component being fabricated and the mechanical stress that the at least one subsection of the tailored fiber placement component will be subject to when the tailored fiber placement component is exposed to the one or more forces and the one or more loads associated with the intended use of the tailored fiber placement component. 
     
     
       7. The method of  claim 5 , wherein the embroidery system is adapted to independently position a roving pipe and a sewing head in three-dimensions as a function of the predefined pattern and the computed stitch density. 
     
     
       8. The method of  claim 7 , wherein controlling the embroidery system further comprises controlling a speed at which a needle stitches the functional thread to secure to the substrate the portion of the roving corresponding to the at least one subsection of the tailored fiber placement component, wherein a rate at which one or more individual stitches are executed is controlled as a function of the at least one physical or mechanical property and the comparative analysis.